In LASIQ I will develop, for the first time, an on-chip titanium-sapphire mode-locked laser capable of generating low-noise optical
frequency combs in the 650-1100 nm wavelength range.
Optical frequency comb generators are light sources capable of generating a spectrum of millions of equally spaced laser lines. Such
light sources allow to down-convert optical frequencies (THz) to the microwave domain (GHz), enabling precision laser spectroscopy
and the construction of optical atomic clocks. Theodor Hänsch and John Hall were awarded the Nobel Prize in physics of 2005 for
developing the optical frequency comb in recognition of its impact on quantum metrology, timekeeping and fundamental physics.
Since their initial development, they have revolutionized several other fields such as LIDAR (light detection and ranging), molecular
spectroscopy, astronomic spectroscopy for exoplanet identification and ultra-low-noise microwave generation.
However, high-performance optical frequency combs are mostly based on expensive (>100 kEUR) and bulky (> 900 cm3) free-space
or fiber-based mode-locked laser systems, which strongly limits their use in real-world applications. This has spurred an enormous
research effort towards developing on-chip optical frequency comb generators. Currently, a large variety of integrated optical comb
generators have been demonstrated, ranging from soliton microcombs to semiconductor mode-locked lasers. However, so far
integrated optical comb generators cannot rival the performance of their table-top counterparts, severely limiting their application. In
LASIQ, I will address this need by demonstrating titanium-sapphire mode-locked lasers on a millimeter-sized chip with a performance
similar to that of the incumbent free-space solution.
The realization of an on-chip titanium-sapphire mode-locked laser will enable chip-scale supercontinuum sources, integrated optical
coherence tomography systems, on-chip optical atomic clocks and dual-comb metrology.